July 3, 2025

These 11 features work better if you go to bed with your Garmin smartwatch on your wrist.

Whether you realize it or not, a lot is happening in your body while you’re sleeping. Your nerve cells reorganize, your body repairs cells, your energy levels are restored, and molecules such as hormones and proteins are released — all as you cycle through different sleep phases.

It makes sense, then, that if you want the most complete picture of how well your body is operating, you’ll want to track your physiological metrics during sleep. That’s why it’s so important to wear your Garmin sleep tracking smartwatch to bed. Not only can you take advantage of features such as sleep score or the built-in alarm clock, but you’ll also see accuracy improvements for other data that require round-the-clock monitoring to give a true picture of how your body is functioning.

Let’s walk through some of the Garmin smartwatch features (which vary by device) that sleep impacts.

OK, so this one is obvious. Garmin smartwatches are good, but they aren’t analyze-your-sleep-quality-from-the-drawer-in-your-nightstand good. You must wear your watch for it to do its job. And we recommend that you pay attention to your sleep habits over time. Sleep is an essential function directly linked to physical and mental health, and consistently not getting enough of it is associated with high blood pressure, heart disease, stroke, poor mental health and Type 2 diabetes, according to the Centers for Disease Control.

Advanced sleep tracking uses your heart rate, heart rate variability (HRV) and body movement data to monitor when you fell asleep and woke up (even any times you were awake during the night). It also looks at when you were in the light, deep and rapid eye movement (REM) sleep stages and for how long. Plus, your baseline readings and age add context, improving the reliability of this feature. Select Garmin smartwatches also track your respiration rate and blood oxygen saturation¹ (more on that later).

Checking your Garmin sleep score² each morning will give you a rating of how well you slept during the night. Curious to see where you fit in with your peers in terms of sleep stats? We analyzed how well Garmin users sleep, and you can even compare yourself to the top Garmin athletes.

Garmin sleep coach on compatible smartwatches uses 5 factors to estimate how much sleep you need in 10-minute intervals between 7 and 9 hours of sleep: age, daily and longer-term activity levels, recent sleep history, naps and HRV. Simply check your compatible Garmin smartwatch when you wake up in the morning and sleep coach will tell you how much sleep you’ll need for the upcoming night. What if you take a nap or go on a long, challenging run? Sleep coach will account for that and update your estimate.

A feature unique to Garmin smartwatches, Body Battery is a real-time look at your personal energy resources. Your Body Battery measurement reflects your physical activity, stress, rest and sleep — and how each impacts your energy levels. On a scale of 1–100, your Body Battery number will indicate how ready you are to tackle a challenge at any given point, or how ready you are to rest. And since quality sleep is the body’s most valuable time for recovery, you’ll need to wear your watch for it to monitor just how effective that recovery is for recharging your Body Battery.

Garmin smartwatches provide all-day heart monitoring data² using an optical sensor built into the back of your device. It detects your heart rate by shining a green light through your skin, which is reflected by the red cells in your skin’s blood vessels. There are many important reasons to track your heart rate, and knowing your resting heart rate (RHR) is one of them.

Your RHR is the number of times your heart beats per minute (bpm) while your body is in a state of rest. Garmin wearables typically measure RHR while you sleep, usually not long before you wake up. For normal adults, the RHR can vary between 60 and 100 bpm, although Garmin data shows that the more active a person is, the lower their RHR tends to be. A lower RHR typically reflects cardiorespiratory fitness, quality sleep and low stress — but you must wear your watch during sleep to get the most accurate reading. 

HRV is another meaningful metric that Garmin technology uses your heart rate to measure¹. You may not have realized it, but your heart doesn’t actually beat regularly — it’s not a metronome. There are varying lengths of time between each heartbeat, and while those changes aren’t typically dramatic, they do provide significant information about your body. Your nervous system regulates these changes in time, and changes in HRV status can reveal how well your body is responding to stress and to relaxation. Analyzing these shifts…